Buggy code:
private Object [ ] getCategoryChildren ( String categoryId ) { } private boolean parentIsInSameCategory ( ColorDefinition definition ) { } private boolean parentIsInSameCategory ( FontDefinition definition ) { } public Object getParent ( Object element ) { } public boolean hasChildren ( Object element ) { } public Object [ ] getElements ( Object inputElement ) { } public void dispose ( ) { } public void inputChanged ( Viewer viewer , Object oldInput , Object newInput ) { } } private class PresentationLabelProvider extends LabelProvider implements IFontProvider { private HashMap fonts = new HashMap ( ) ; private HashMap images = new HashMap ( ) ; private int imageSize = - 1 ; private int usableImageSize = - 1 ; private IPropertyChangeListener listener = new IPropertyChangeListener ( ) { public void propertyChange ( PropertyChangeEvent event ) { } } ; private Image emptyImage ; public PresentationLabelProvider ( ) { } public void hookListeners ( ) { } public void dispose ( ) { } public void clearFontCache ( ) { } public Font getFont ( Object element ) { } public Image getImage ( Object element ) { } private void ensureImageSize ( Display display ) { } public String getText ( Object element ) { } private boolean isDefault ( IThemeElementDefinition def ) { } } private static final ResourceBundle RESOURCE_BUNDLE = ResourceBundle . getBundle ( ColorsAndFontsPreferencePage . class . getName ( ) ) ; private Map categoryMap = new HashMap ( 7 ) ; private Font appliedDialogFont ; private Composite colorControls ; private Map colorPreferencesToSet = new HashMap ( 7 ) ; private CascadingColorRegistry colorRegistry ; private Button colorResetButton ; private ColorSelector colorSelector ; private Map colorValuesToSet = new HashMap ( 7 ) ; private Composite controlArea ; private StackLayout controlAreaLayout ; private Composite defaultPreviewControl ; private Text descriptionText ; private List dialogFontWidgets = new ArrayList ( ) ; private Button fontChangeButton ; private Composite fontControls ; private Map fontPreferencesToSet = new HashMap ( 7 ) ; private CascadingFontRegistry fontRegistry ; private Button fontResetButton ; private Button fontSystemButton ; private Map fontValuesToSet = new HashMap ( 7 ) ; private Composite previewComposite ; private Map previewMap = new HashMap ( 7 ) ; private Set previewSet = new HashSet ( 7 ) ; private StackLayout stackLayout ; private final IThemeRegistry themeRegistry ; private ITheme currentTheme ; private ColorsAndFontsPreferencePage . PresentationLabelProvider labelProvider ; private CascadingTheme cascadingTheme ; private IPropertyChangeListener themeChangeListener ; private Workbench workbench ; private FilteredTree tree ; public ColorsAndFontsPreferencePage ( ) { } private static boolean equals ( String string , String string2 ) { } private Button createButton ( Composite parent , String label ) { } private void createColorControl ( ) { } protected Control createContents ( Composite parent ) { } private void createDescriptionControl ( Composite parent ) { } private void createFontControl ( ) { } private void createTree ( Composite parent ) { } private void createPreviewControl ( Composite mainColumn ) { } public void dispose ( ) { } private void clearPreviews ( ) { } private ColorDefinition getColorAncestor ( ColorDefinition definition ) { } private RGB getColorAncestorValue ( ColorDefinition definition ) { } private RGB getColorValue ( ColorDefinition definition ) { } private Composite getDefaultPreviewControl ( ) { } private ColorDefinition [ ] getDescendantColors ( ColorDefinition definition ) { } private FontDefinition [ ] getDescendantFonts ( FontDefinition definition ) { } private FontDefinition getFontAncestor ( FontDefinition definition ) { } private FontData [ ] getFontAncestorValue ( FontDefinition definition ) { } protected FontData [ ] getFontValue ( FontDefinition definition ) { } protected ColorDefinition getSelectedColorDefinition ( ) { } protected FontDefinition getSelectedFontDefinition ( ) { } private void hookListeners ( ) { } public void init ( IWorkbench aWorkbench ) { this . workbench = ( ( Workbench ) ( aWorkbench ) ) ; <START_BUG> setPreferenceStore ( workbench . getPreferenceStore ( ) ) ; <END_BUG> final IThemeManager themeManager = aWorkbench . getThemeManager ( ) ; themeChangeListener = new IPropertyChangeListener ( ) { public void propertyChange ( PropertyChangeEvent event ) { if ( event . getProperty ( ) . equals ( IThemeManager . CHANGE_CURRENT_THEME ) ) { updateThemeInfo ( themeManager ) ; refreshCategory ( ) ; } } } ; themeManager . addPropertyChangeListener ( themeChangeListener ) ; updateThemeInfo ( themeManager ) ; } private void updateThemeInfo ( IThemeManager manager ) { } private boolean isDefault ( ColorDefinition definition ) { } private boolean isDefault ( FontDefinition definition ) { } private void myApplyDialogFont ( Control control ) { } protected void performApply ( ) { } private void performColorDefaults ( ) { } private boolean performColorOk ( ) { } protected void performDefaults ( ) { } private void performFontDefaults ( ) { } private boolean performFontOk ( ) { } public boolean performOk ( ) { } private void refreshCategory ( ) { } private boolean resetColor ( ColorDefinition definition ) { } protected boolean resetFont ( FontDefinition definition ) { } protected void setColorPreferenceValue ( ColorDefinition definition , RGB newRGB ) { } private void setDescendantRegistryValues ( ColorDefinition definition , RGB newRGB ) { } private void setDescendantRegistryValues ( FontDefinition definition , FontData [ ] datas ) { } protected void setFontPreferenceValue ( FontDefinition definition , FontData [ ] datas ) { } protected void setRegistryValue ( ColorDefinition definition , RGB newRGB ) { } protected void setRegistryValue ( FontDefinition definition , FontData [ ] datas ) { } protected void swapColorControls ( ) { } protected void swapFontControls ( ) { } protected void swapNoControls ( ) { } private void updateCategorySelection ( ThemeElementCategory category ) { } private IThemePreview getThemePreview ( ThemeElementCategory category ) throws CoreException { } private ITheme getCascadingTheme ( ) { } protected void updateColorControls ( ColorDefinition definition ) { } protected void updateFontControls ( FontDefinition definition ) { } private void updateForDialogFontChange ( Font newFont ) { } private void restoreTreeSelection ( ) { } private void saveTreeSelection ( ) { } private void restoreTreeExpansion ( ) { }

Fix:
setPreferenceStore ( PrefUtil . getInternalPreferenceStore ( ) ) ;